I just got back from Tijuana for my 3rd fill yesterday. I parked at the border, caught a cab, got my fill, cab back to border and walked back through. NOW if there was a cause for concern of the Swine Flu coming through Tijuana, I believe all the border agents checking my passports and my citizenship would have been wearing face masks and guess what? They were not!
As far as medical attention in Mainland Mexico and Baja Californa, depending on how far into mainland people are, YES their medical facilities are poor. Mexico is a poor, third world country. All of us see the resort areas as tourist and of course that is going to have the best of the best medical facilities.